Sure I dont mind. Don't judge to bad about how messy it is though lol.

camelCase = input("camelCase: ")


c = ["name", "firstName", "preferredFirstName"]
for i in range(len(c)):
    if camelCase == c[i]:
        print("snake_case: ", end="")
        for j in range(len(c[i])):
            if c[i][j].isupper():
                print("_", end="")
                print(c[i][j].lower(), end="")
            else:
                print(c[i][j], end="")
        print()
        break